JP2004193773A - Image read apparatus and unit used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image read apparatus capable of avoiding a defect such as the breakage of a wire interconnecting a wiring pattern on a circuit board with an IC chip, and simplifying the wiring pattern. <P>SOLUTION: An image read apparatus X is provided with: a light source 1; a case 2 for accommodating the light source 1 therein; a board 8 having first and second side edges 8a, 8b spaced in the width direction and assembled to the case 2; a plurality of sensor IC chips 7 mounted on the board 8 toward the second side edge 8a from the center of the board 8 in the width direction; and a plurality of wires W led from the plurality of sensor IC chips 7 onto a wiring pattern 9 formed on the board 8 to electrically interconnect them. Each wire W is led from each sensor IC chip 7 to the first side edge 8a of the board 8. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image reading apparatus used for reading an image of a document and other desired images, and a unit used for the same.
[0002]
[Prior art]
As an example of a conventional image reading apparatus, there is one described in Patent Document 1. As shown in FIG. 6 of the present application, the image reading device described in Patent Document 1 includes a substrate 100 on which a plurality of light sources 101 and a plurality of sensor IC chips 102 are mounted on an upper surface, and this substrate 100 is assembled. And a case 200 provided.
[0003]
The plurality of light sources 101 are arranged at regular intervals along the first side edge 100a of the substrate 100, and are located near the first side edge 100a. In the case 200, an optical path 201 for allowing light emitted from the light source 101 to reach the image reading area S is formed. The sensor IC chip 102 is provided near the second side edge 100b of the substrate 100 because the optical path 201 is formed above the substrate 100. The sensor IC chip 102 has a light receiving unit 102a, and the light reflected by the surface of the document D on the image reading area S is focused on the light receiving unit 102a by passing through the lens 105. .
[0004]
The sensor IC chip 102 has a photoelectric conversion function, and is configured to output an image signal of an output level corresponding to the amount of received light. Therefore, if the light receiving unit 102a receives extra light, it is impossible to output an appropriate image signal. Therefore, in order to prevent the light receiving unit 102a from directly receiving the light emitted from the light source 101, the case 200 is formed with a wall 202 that partitions between the light source 101 and the sensor IC chip 102. The wall portion 202 is in contact with the upper surface of the substrate 100 and extends in the longitudinal direction of the substrate 100.
[0005]
On the upper surface of the substrate 100, a wiring pattern (not shown) for electrically connecting the light source 101 and the sensor IC chip 102 to the connector 103 attached to the substrate 100 is formed. The image signal and the like are output to an external device via the connector 103.
[0006]
[Patent Document 1]
JP 2001-339574 A
[Problems to be solved by the invention]
In the above-described conventional image reading apparatus, the wires W are used to connect the wiring pattern to the sensor IC chip 102. The wire W is provided so as to be drawn out from the sensor IC chip 102 to the second side edge 100b side of the substrate 100. This is to avoid interference between the wire W and the wall 202. However, such a configuration has the following problems.
[0008]
First, in the above configuration, the wire W is located on or near the first side edge 100a of the substrate 100. Therefore, for example, when assembling the substrate 100 to the case 200, the hand of the worker or the case 200 easily comes into contact with the wire W, and the wire W may be broken.
[0009]
Second, the wiring pattern is provided by effectively using a wider area of the upper surface of the substrate 100 closer to the first side edge 100a than the sensor IC chip 102. However, the pad for wire bonding provided in the wiring pattern must be provided in a region closer to the second side edge 100b than the sensor IC chip 102 in accordance with the drawing direction of the wire W from the sensor IC chip 102. No. For this reason, it is necessary to draw more wiring from the area closer to the first side edge 100a than the sensor IC chip 102 to the area closer to the second side edge 100b, which complicates the wiring pattern and reduces the manufacturing cost. Had become expensive.
[0010]
The present invention has been conceived under such circumstances, and can solve problems such as breakage of a wire connecting a wiring pattern on a substrate and a sensor IC chip. It is an object of the present invention to provide an image reading device capable of simplifying a pattern and a unit used for the image reading device.
[0011]
DISCLOSURE OF THE INVENTION
In order to solve the above problems, the present invention takes the following technical measures.
[0012]
An image reading device provided by a first aspect of the present invention includes a light source for illuminating an image reading area, a case accommodating the light source therein, and a first side edge portion spaced apart in a width direction. And a substrate attached to the case, mounted on the case closer to the second side edge than the center in the width direction on the substrate, and from the image reading area. A plurality of sensor IC chips for receiving the traveling light; and a plurality of wires which are drawn out from the plurality of sensor IC chips onto a wiring pattern formed on the substrate and electrically connect these. An image reading apparatus, wherein each of the wires is drawn from the sensor IC chip to a first side edge of the substrate.
[0013]
According to such a configuration, since the wires are arranged closer to the center in the width direction of the board as compared with the related art, for example, when assembling the board to the case, the hand of the operator is required. And the case hardly comes into contact with the wire. Therefore, it is possible to prevent the wire from breaking.
[0014]
Further, according to the above configuration, since the wires are drawn out from the sensor IC chips to the first side edge of the substrate, the wire bonding pads provided in the wiring pattern are provided in the sensor IC chips. It is arranged in a wider area closer to the first side edge than the IC chip. In this way, if the wiring pattern is formed in the wide area, unlike the related art, many wirings are drawn into the narrow area closer to the second side edge than each of the sensor IC chips. There is no need. This makes it possible to simplify the wiring pattern and reduce manufacturing costs.
[0015]
In a preferred embodiment of the present invention, the apparatus further comprises a light guide for guiding light emitted from the light source to the image reading area, and the case includes the light guide and the sensor IC chips. Is formed so as to be spaced from the substrate.
[0016]
According to such a configuration, the wire can be arranged in the gap between the wall and the substrate. Therefore, it is suitable for avoiding a problem that the wire interferes with the wall.
[0017]
A unit provided by the second aspect of the present invention includes a substrate having a first side edge and a second side edge that are spaced apart in the width direction, and the first and second side edges on the substrate. A plurality of sensor IC chips mounted near the side edge portion of the second and a plurality of wires drawn out from the plurality of sensor IC chips onto a wiring pattern formed on the substrate and electrically connecting them; Wherein the wires are led out from the sensor IC chip to the first side edge of the substrate.
[0018]
According to such a configuration, it can be suitably used for the image reading device provided by the first aspect of the present invention, and the same effects as those described for the image reading device can be obtained.
[0019]
In a preferred embodiment of the present invention, a plurality of pads to which the wires are bonded are provided on a surface of each of the sensor IC chips. Rather than the first side edge of the substrate. According to such a configuration, the wire bonding operation can be easily performed.
[0020]
Other features and advantages of the present invention will become more apparent from the following description of embodiments of the present invention.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.
[0022]
1 to 4 show an example of the image reading apparatus according to the present invention. The image reading apparatus X of the present embodiment includes a case 2, a light guide 3, a reflector 4, a transparent plate 5, a lens array 6, and a unit U. The unit U has a configuration in which the light source 1 and a plurality of sensor IC chips 7 are mounted on the upper surface 81 of an elongated rectangular substrate 8 extending in the main scanning direction (the direction of arrow A in FIG. 1).
[0023]
The light source 1 is for illuminating the image reading area S, and in the present embodiment is configured by LEDs that emit light of three colors, red, green, and blue, respectively. The light source 1 is located near the first side edge 8 a near one end in the longitudinal direction of the substrate 8.
[0024]
The case 2 has a substantially block shape made of a synthetic resin, and a substrate 8 is attached to a lower surface of the case 2. As shown in FIG. 2, the case 2 includes a first space 21 that houses the light source 1, a second space 23 that houses a plurality of sensor IC chips 7, a light guide 3, A third space 23 that accommodates the reflector 4 is formed. The first space 21 and the second space 22 are separated by a first wall 24 extending in the lateral direction of the case 2. The second space 22 and the third space 23 are separated by a second wall 25. The second wall 24 is located above the substrate 8 and is spaced from the substrate 8. The first and second walls 24 and 25 block light traveling from the light source 1 directly to the sensor IC chip 7.
[0025]
The light guide 3 is a highly transparent member made of, for example, PMMA (polymethyl methacrylate). As shown in FIG. 2, the light guide 3 extends in the longitudinal direction of the case 2 and has an auxiliary region 31 at one end in the longitudinal direction and a main region 32 other than the auxiliary region 31. The auxiliary region 31 has a light incident surface 31 a facing the light source 1, and makes the light incident on the light incident surface 31 a travel into the main region 32. The main region 32 travels in the longitudinal direction of the light guide 3 while totally reflecting light traveling from the auxiliary region 31. On the lower surface of the main region 32, a plurality of recesses (not shown) are provided at predetermined intervals in the longitudinal direction. When the light traveling in the main area 21 enters each of the concave portions, the light is scattered and reflected in various directions, and can be emitted from the light emitting surface 32a toward the image reading area S. Thus, the image reading area S is illuminated.
[0026]
The reflector 4 is made of, for example, a white synthetic resin having a high light reflectance, has a housing portion 41 for housing the light guide 3, and is disposed on the second wall portion 25. The reflector 4 covers portions other than the light entrance surface 31a and the light exit surface 32a of the light guide 3, and plays a role in preventing unnecessary leakage of light from the light guide 3.
[0027]
The transparent plate 5 is made of synthetic resin or glass, and is attached to the upper surface of the case 2. The transparent plate 5 serves as a document guide when the document D is conveyed in the sub-scanning direction (the direction of arrow B in FIGS. 3 and 4) by the platen roller P, for example.
[0028]
The lens array 6 is provided between the second space portion 22 and the third space portion 23 of the case 2 as well shown in FIGS. In the lens array 6, a large number of lenses 62 for image formation are held in a row in a holder 61 made of a synthetic resin and formed in a block shape extending in the main scanning direction. An area on the surface of the transparent plate 5 facing the lens 62 is an image reading area S extending in the main scanning direction.
[0029]
The plurality of sensor IC chips 7 are semiconductor chips having a substantially rectangular shape in plan view. The plurality of sensor IC chips 7 are linearly arranged along the second side edge 8b of the substrate 8, and are disposed near the second side edge 8b. Therefore, the upper surface 81 of the substrate 8 has a wider first region 81a closer to the first side edge 8a than each sensor IC chip 7 and a wider first region 81a closer to the second side edge 8b than each sensor IC chip 7. It is divided into a narrow second region 81b. The sensor chip 7 has a light receiving section 71 on which light passing through the lens 62 is focused. The sensor IC chip 7 has a photoelectric conversion function, and is configured to output an image signal having an output level corresponding to the amount of received light.
[0030]
In addition, a plurality of pads 72 are provided on the upper surface of the sensor IC chip 7, as shown in FIG. The pads 72 are arranged closer to the first side edge 8a than the center of the sensor IC chip 7 in the width direction. Specific examples of the plurality of pads 72 include pads 72 (Vcc) and 72 (VREF) for voltage application, pads 72 (GND) for ground connection, and pads 72 (CLK) and 72 for input or output of various signals. (SI), 72 (SP), 72 (AO), 72 (SO), and the like. When a serial-in signal is input to the pad 72 (SI), the sensor IC chip 7 discharges the charge stored in the light receiving section 71 and serially outputs the charge to the pad 72 (AO). I have.
[0031]
The board 8 is made of ceramic, for example, and a connector 10 is attached to the first side edge 8a. The connector 10 is electrically connected to the light source 1 and the sensor IC chip 7 via the wiring pattern 9. The wiring pattern 9 includes a plurality of wirings corresponding to the plurality of pads 72. Each wiring is connected to each pad 72 via a wire W. Wirings other than those for the pads 72 (GND), 72 (AO), and 72 (VREF) are provided only in the wide first region 81a, and a connection portion with the wire W is also provided in the first region 81a. I have. On the other hand, three wires for the pads 72 (GND), 72 (AO), and 72 (VREF) are provided across the first region 81a and the second region 81b. However, the connection portions of these three wires with the wires W are arranged in the first region 81a, like the other wires. Thus, all of the plurality of wires W are provided so as to be drawn out from the sensor IC chip 7 toward the first side edge 8a.
[0032]
Next, the operation of the image reading device X will be described.
[0033]
In the image reading apparatus X, in order to perform the reading process of the image of the document D, the image reading area S is first illuminated by illuminating the light source 1. Then, the light reflected by the surface of the document D on the image reading area S is focused by passing through the lens 62, and the image of the document D is formed on the light receiving unit 71. The sensor IC chip 7 serially outputs an analog image signal corresponding to the amount of light received by the light receiving section 71, and this image signal is output to an external device via the connector 10.
[0034]
In the image reading device X of the present embodiment, the wire W is drawn out from the sensor IC chip 7 to the first side edge 8a side, and is disposed closer to the center in the width direction of the substrate 8 as compared with the above-described conventional technology. ing. For this reason, for example, when assembling the substrate 8 to the case 2, it is difficult for the worker's hand or the case 2 to come into contact with the wire W, and it is possible to prevent the wire W from being broken. While the wire connection target portion of the wiring pattern 9 is provided in the first region 81a of the substrate 8, each pad 72 of the sensor IC chip 7 is closer to the first region 81a of the substrate 8 on the sensor IC chip 7. , The wire bonding operation for them can be easily performed. Further, since the wire W can be arranged in the gap between the second wall 25 and the substrate 1, it is suitable for avoiding interference between the wire W and the second wall 25.
[0035]
In the image reading device X, since the wires W are drawn out from the sensor IC chip 7 to the first side edge 8a side, unlike the above-described conventional technology, many wires provided in the first region 81a are connected. It is no longer necessary to draw in the second area 81b. Thereby, the wiring pattern 9 can be simplified, and the manufacturing cost can be reduced.
[0036]
The present invention is not limited to the contents of the above-described embodiment. The specific configuration of each part of the image reading apparatus according to the present invention and the unit used therein can be variously changed in design.
[0037]
In the present invention, for example, the case in which the unit is assembled is not limited to the case in which the wall part separating the second space part and the third space part is spaced from the substrate. The case may be configured such that the wall portion abuts on the upper surface of the substrate as in the case of the related art. Even in this case, the wires can be provided so as to be drawn out from the sensor IC chip to the first side edge. Further, the present invention is not limited to the configuration including one light source and the light guide, and may include a plurality of light sources without the light guide.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an embodiment of an image reading apparatus according to the present invention.
FIG. 2 is a sectional view taken along line II-II of FIG.
FIG. 3 is a sectional view taken along the line III-III of FIG. 2;
FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;
FIG. 5 is a plan view showing an embodiment of the unit according to the present invention.
FIG. 6 is a cross-sectional view showing an example of the related art.
[Explanation of symbols]
Reference Signs List 1 light source 2 case 25 second wall 3 light guide 7 sensor IC chip 71 light receiving section 72 pad 8 substrate 8a first side edge 8b second side edge 9 wiring pattern W wire X image reading device U unit

Claims (4)

A light source for illuminating the image reading area, a case accommodating the light source therein, a first side edge and a second side edge spaced apart in the width direction, and the case A plurality of sensor IC chips mounted nearer to the second side edge than the center in the width direction on the substrate and receiving light traveling from the image reading area; A plurality of wires drawn out from the sensor IC chip onto a wiring pattern formed on the substrate and electrically connecting these wires,
The image reading device, wherein each of the wires is drawn from the sensor IC chip to a first side edge of the substrate. It further comprises a light guide for guiding the light emitted from the light source to the image reading area,
The image reading device according to claim 1, wherein a wall portion separating the light guide and each of the sensor IC chips is formed in the case so as to be spaced from the substrate. A substrate having a first side edge and a second side edge spaced apart in the width direction; and a plurality of sensor ICs mounted closer to the second side edge than the center in the width direction on the substrate. A unit comprising: a plurality of chips; and a plurality of wires drawn out from the plurality of sensor IC chips onto a wiring pattern formed on the substrate and electrically connecting the plurality of sensor IC chips,
The unit, wherein each of the wires is drawn from the sensor IC chip to the first side edge of the substrate. A plurality of pads to which the wires are bonded are provided on the surface of each of the sensor IC chips,
The unit according to claim 3, wherein the plurality of pads are arranged closer to a first side edge of the substrate than a center in a width direction of each of the sensor IC chips.

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